KR20160054616A - Managing reserved cells and user equipments in an mbsfn environment within a wireless communication system - Google Patents

Abstract

In a first configuration, the device determines, in a radio frame, the subframes used by one or more neighboring BSs to provide services and sends information indicative of the determined subframes to the UE. In a second configuration, the apparatus determines, in a radio frame, the subframes used by one or more neighboring BSs to provide services, and in a radio frame, in the remaining subframes other than the determined subframes Determines the second power based on the first power and transmits the second power in a subset of the determined subframes of symbols such that the difference between the first power and the second power is less than the threshold . In a third configuration, the apparatus is configured to receive, in a radio frame, information indicative of subframes used by one or more neighbor BSs to provide services and to adjust AGC gain based on the displayed subframes do.

Description

TECHNICAL FIELD [0001] The present invention relates to management of cells and user equipments reserved in an MBSFN environment in a wireless communication system,

This application is related to U.S. Provisional Application Serial No. 61 / 482,910, filed May 5, 2011, entitled " METHOD AND APPARATUS FOR MANAGING MULTICAST / BROADCAST SINGLE FREQUENCY NETWORK (MBSFN) AREA RESERVED CELLS IN A WIRELESS COMMUNICATION SYSTEM " , And U.S. Patent Application Serial No. 13 / 461,602, filed May 1, 2012, entitled " MANAGING RESERVED CELLS AND USER EQUIPMENTS IN AN MBSFN ENVIRONMENT WITHIN A WIRELESS COMMUNICATION SYSTEM, "Quot; is expressly incorporated herein by reference in its entirety.

[0001] This disclosure relates generally to communication systems, and more particularly to managing reserved cells and user equipment (UEs) in a multicast broadcast single frequency network (MBSFN) environment within a wireless communication system .

Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephony, video, data, messaging and broadcasts. Conventional wireless communication systems can utilize multiple access technologies that can support communication with multiple users by sharing available system resources (e.g., bandwidth and transmit power). Examples of such multiple access techniques include, but are not limited to, code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, Carrier frequency division multiple access (SC-FDMA) systems and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access technologies have been employed in a variety of telecommunications standards to provide a common protocol that allows different wireless devices to communicate at city, country, province, and even global levels. An example of emerging telecommunication standards is Long Term Evolution (LTE). LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP). LTE can better support mobile broadband Internet access, reduce costs, improve services, utilize the new spectrum, improve the spectrum efficiency, and improve the performance of OFDMA in uplink (DL), uplink Is designed to better integrate with other open standards using FDMA and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to increase, there is a need for further improvements in LTE technology. Advantageously, these improvements should be applicable to other multi-access technologies and telecommunications standards using these technologies.

In the aspects of this disclosure, methods, computer program products and apparatus are provided. The device may be a base station. The device determines, in a radio frame, the subframes used by one or more neighboring base stations to provide services. The device sends information indicating the determined subframes to the UE.

In the aspects of this disclosure, methods, computer program products and apparatus are provided. The device may be a base station. The device determines, in a radio frame, the subframes used by one or more neighboring base stations to provide services. The apparatus transmits at the first power in the remaining subframes other than the subframes determined in the radio frame. The apparatus determines the second power based on the first power such that the difference between the second power and the first power is less than the threshold. The second power is less than the first power. The apparatus transmits at a second power in a subset of the symbols of the determined subframes.

In the aspects of this disclosure, methods, computer program products and apparatus are provided. The device may be a UE. The device receives from the base station information indicative of subframes used by one or more neighboring base stations to provide services in a radio frame. The apparatus adjusts the AGC gain based on the displayed sub-frames.

1 is a diagram showing an example of a network architecture.
2 is a diagram showing an example of an access network.
3 is a diagram showing an example of a DL frame structure in LTE.
4 is a diagram showing an example of an UL frame structure in LTE.
5 is a diagram illustrating an example of a radio protocol architecture for user and control planes.
6 is a diagram illustrating an example of an evolved Node B (eNB) and user equipment in an access network.
7 is a diagram illustrating an evolved multicast broadcast multimedia service in a multi-media broadcast over a single frequency network.
Figure 8 is a first diagram for illustrating exemplary methods.
9 is a second diagram for illustrating exemplary methods.
10 is a flow diagram of a first method of wireless communication.
11 is a flow diagram of a second method of wireless communication.
12 is a flowchart of a third method of wireless communication.
13 is a flowchart of a fourth method of wireless communication.
14 is a conceptual data flow diagram illustrating the flow of data between different modules / means / components in an exemplary eNB device.
15 is a diagram showing an example of a hardware implementation for an eNB device using a processing system.
16 is a conceptual data flow diagram illustrating data flow between different modules / means / components in an exemplary UE device.
17 is a diagram illustrating an example of a hardware implementation for a UE device using a processing system.

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order not to obscure the concepts.

Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These devices and methods are described in the following detailed description by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as " Will be shown in the accompanying drawings. These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented in hardware or software depends upon the particular application and design constraints imposed on the overall system.

For example, an element, or any combination of any element or elements of the element, may be implemented as a "processing system" comprising one or more processors. Examples of processors are microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic , Discrete hardware circuits, and other suitable hardware configured to perform various functions described throughout this disclosure. One or more processors of the processing system may execute the software. The software may include instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, firmware, middleware, microcode, hardware description language, , Which are intended to be broadly interpreted as referring to a plurality of applications, applications, software applications, software packages, routines, subroutines, objects, executables, execution threads, procedures,

Thus, in one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on one or more instructions or code on a computer readable medium, or encoded as one or more instructions or code. Computer readable media include computer storage media. The storage medium may be any available media that can be accessed by a computer. For example, such computer-readable media may store program code required in the form of RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or instructions or data structures Or any other medium that can be used to carry or carry data and which can be accessed by a computer. As used herein, a disc and a disc may be a compact disc (CD), a laser disc, an optical disc, a digital versatile disc (DVD), a floppy disc, And Blu-ray discs, wherein discs usually reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of the above should also be included within the scope of computer readable media.

FIG. 1 is a diagram illustrating an LTE network architecture 100. FIG. The LTE network architecture 100 may be referred to as an evolved packet system (EPS) 100. EPS 100 may include one or more user equipments (UEs) 102, an evolved UMTS terrestrial radio access network (E-UTRAN) 104, an evolved packet core (EPC) 110, a home subscriber server (HSS) 120 and an operator's IP services 122. The EPS may be interconnected with other access networks, but for simplicity, these entities / interfaces are not shown. As shown, EPS provides packet-switching services, but as will be readily appreciated by those skilled in the art, the various concepts presented throughout this disclosure may be extended to networks that provide circuit-switched services .

The E-UTRAN includes an evolved Node B (eNB) 106 and other eNBs 108. The eNB 106 provides user and control plane protocol terminations to the UE 102. eNB 106 may be connected to other eNBs 108 via a backhaul (e.g., X2 interface). The eNB 106 may also be referred to as a base station, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a base service set (BSS), an extended service set (ESS) The eNB 106 provides the UE 102 with an access point to the EPC 110. Examples of UEs 102 include a cellular telephone, a smart phone, a Session Initiation Protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, For example, an MP3 player), a camera, a game console, or any other similar function device. The UE 102 may also be coupled to a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, , A mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other appropriate term.

The eNB 106 is connected to the EPC 110 by an S1 interface. EPC 110 includes a Mobility Management Entity (MME) 112, other MMEs 114, a serving gateway 116, and a packet data network (PDN) gateway 118. The MME 112 is a control node that processes signaling between the UE 102 and the EPC 110. In general, the MME 112 provides bearer and connection management. All user IP packets are sent via the serving gateway 116, which is itself connected to the PDN gateway 118. The PDN gateway 118 provides UE IP address assignment as well as other functions. The PDN gateway 118 is connected to the IP services 122 of the operator. The operator's IP services 122 may include the Internet, an Intranet, an IP Multimedia Subsystem (IMS), and a PS Streaming Service (PSS).

2 is a diagram illustrating an example of an access network 200 in an LTE network architecture. In this example, the access network 200 is divided into a plurality of cellular zones (cells) 202. ENBs 208 of one or more lower power classes may have cellular zones 210 overlapping one or more of the cells 202. ENB 208 of the lower power class may be a femtocell (e.g., a home eNB (HeNB)), a picocell, a microcell or a remote radio head (RRH). Macro eNBs 204 are each assigned to each cell 202 and are configured to provide access points to the EPCs 110 to all UEs 206 in the cells 202. Although there is no centralized controller in the example access network 200, a centralized controller may be used in alternative configurations. The eNBs 204 are responsible for all radio related functions including radio bearer control, admission control, mobility control, scheduling, security, and connectivity to the serving gateway 116.

The modulation and multiple access schemes used by access network 200 may vary according to the particular telecommunication standard being used. In LTE applications, OFDM is used for DL and SC-FDMA is used for UL to support both frequency division duplexing (FDD) and time division duplexing (TDD). As will be readily appreciated by those skilled in the art from the following detailed description, the various concepts presented herein are well suited for LTE applications. However, these concepts can be easily extended to other telecommunication standards using different modulation and multiple access techniques. For example, these concepts can be extended to Evolution-Data Optimization (EV-DO) or Ultra Mobile Broadband (UMB). EV-DO and UMB are air interface standards promulgated by the 3rd Generation Partnership Project 2 (2GPP2) as part of the CDMA2000 standards family and use CDMA to provide broadband Internet access for mobile stations. These concepts also include Universal Terrestrial Radio Access (UTRA), which utilizes other variants of CDMA, such as Wideband-CDMA (W-CDMA) and TD-SCDMA; A general purpose system for mobile communication (GSM) using TDMA; And Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20 and FLASH OFDM using OFDMA. UTRA, E-UTRA, UMTS, LTE and GSM are described in documents from the 3GPP framework. CDMA2000 and UMB are described in documents from 3GPP2 mechanism. Actual wireless communication standards and the multiple access techniques used will depend upon the particular application and overall design constraints imposed on the system.

eNBs 204 may have multiple antennas supporting MIMO technology. The use of MIMO technology allows eNBs 204 to utilize the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing can be used to simultaneously transmit different streams of data on the same frequency. Data streams may be transmitted to a single UE 206 to increase the data rate or may be transmitted to multiple UEs 206 to increase the overall system capacity. This is accomplished by spatially precoding each data stream (i.e., applying amplitude and phase scaling), and then transmitting each spatial precoded stream on the DL via multiple transmit antennas. The spatial precoded data streams arrive at the UE (s) 206 with different spatial signatures and the spatial signatures are generated by the UEs 206 each of which is associated with one or more data To restore the streams. On the UL, each UE 206 transmits a spatial precoded data stream, and the space precoded data stream enables the eNB 204 to identify the source of each spatial precoded data stream.

Spatial multiplexing is generally used when channel conditions are good. If channel conditions are less favorable, beamforming may be used to focus the transmit energy in one or more directions. This can be achieved by spatial precoding the transmitted data through a plurality of antennas. To achieve good coverage at the edges of the cell, a single stream beamforming transmission with transmit diversity may be used.

In the following detailed description, various aspects of an access network will be described with reference to a MIMO system supporting OFDM on a DL. OFDM is a spread spectrum technique that modulates data across multiple subcarriers in an OFDM symbol. The subcarriers are spaced apart at the correct frequencies. This interval provides "orthogonality" which allows the receiver to recover data from the subcarriers. In the time domain, a guard interval (e. G., A cyclic prefix) may be added to each OFDM symbol to counter inter-OFDM-symbol interference. UL may use SC-FDMA in the form of a DFT-spread OFDM signal to compensate for a high peak-to-average power ratio (PAPR).

3 is a diagram 300 illustrating an example of a DL frame structure in LTE. The frame (10 ms) may be divided into ten equal-sized sub-frames. Each sub-frame may comprise two consecutive time slots. A resource grid may be used to represent two time slots, each time slot including a resource block. The resource grid is divided into a number of resource elements. In LTE, the resource block includes 12 consecutive subcarriers in the frequency domain and 7 consecutive OFDM symbols in the time domain for a regular cyclic prefix in each OFDM symbol, i. E., Including 84 resource elements do. For the extended cyclic prefix, the resource block contains six consecutive OFDM symbols in the time domain and has 72 resource elements. Some of the resource elements denoted by R 302,304 include DL reference signals (DL-RS). The DL-RS includes a cell-specific RS (CRS) (also sometimes referred to as a common RS) 302 and a UE-specific RS (UE-RS) The UE-RS 304 is transmitted only in the resource blocks to which the corresponding physical DL shared channel (PDSCH) is mapped. The number of bits carried by each resource element depends on the modulation scheme. Thus, the more resource blocks the UE receives and the higher the modulation scheme, the greater the data rate for the UE.

4 is a diagram 400 showing an example of an UL frame structure in LTE. The available resource blocks for the UL may be partitioned into data sections and control sections. The control section may be formed at two edges of the system bandwidth and may have a configurable size. The resource blocks of the control section may be assigned to the UEs for transmission of control information. The data section may include all resource blocks not included in the control section. The UL frame structure allows a data section to contain adjacent subcarriers, which allows a single UE to be allocated all adjacent subcarriers of a data section.

The UE may be allocated resource blocks 410a and 410b of the control section to transmit control information to the eNB. The UE may also be allocated resource blocks 420a and 420b of the data section to transmit data to the eNB. The UE may transmit control information on the physical UL control channel (PUCCH) through allocated resource blocks in the control section. The UE may transmit only data on the physical UL Shared Channel (PUSCH) or all of the data and control information through the allocated resource blocks of the data section. The UL transmission may span both of the two slots of the subframe and may hop across the frequency.

A set of resource blocks may be used to perform initial system access and achieve UL synchronization on a physical random access channel (PRACH) 430. PRACH 430 may carry a random sequence and may not carry any UL data / signaling. Each random access preamble occupies bandwidth corresponding to six consecutive resource blocks. The start frequency is specified by the network. That is, the transmission of the random access preamble is limited to specific time and frequency resources. There is no frequency hopping for PRACH. The PRACH attempt is carried in a single sub-frame (1 ms) or in a sequence of several adjacent sub-frames, and the UE can only make one PRACH attempt per frame (10 ms).

5 is a drawing 500 illustrating an example of a radio protocol architecture for users and control planes in LTE. The radio protocol architecture for the UE and eNB is shown as having three layers: Layer 1, Layer 2 and Layer 3. Layer 1 (the L1 layer) is the lowest layer and implements various physical layer signal processing functions. The L1 layer will be referred to herein as the physical layer 506. Layer 2 (L2 layer) 508 is above the physical layer 506 and is responsible for the link between the UE and the eNB over physical layer 506.

In the user plane, the L2 layer 508 includes a media access control (MAC) lower layer 510, a radio link control (RLC) lower layer 512 and a Packet Data Convergence Protocol (PDCP) lower layer 514, They can be terminated at the eNB at the network side. Although not shown, the UE may terminate at the network side (e.g., the IP layer) terminating at the PDN gateway 118 and at the other end (e.g., far end UE, server, etc.) Lt; RTI ID = 0.0 > layer < / RTI >

The PDCP sublayer 514 provides multiplexing between the different radio bearers and the logical channels. The PDCP lower layer 514 also provides header compression of upper layer data packets to reduce radio transmission overhead, security by encryption of data packets, and handover support between eNBs for UEs. The RLC lower layer 512 may be used to compensate for out-of-order reception due to segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and hybrid automatic repeat request (HARQ) And provides reordering of data packets. The MAC lower layer 510 provides multiplexing between the logic and transport channels. The MAC lower layer 510 is also responsible for allocating various radio resources (e. G., Resource blocks) of one cell among the UEs. The MAC lower layer 510 is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE and the eNB is substantially the same as the architecture for the physical layer 506 and the L2 layer 508, except that there is no header compression capability for the control plane. The control plane also includes a radio resource control (RRC) lower layer 516 at layer 3 (L3 layer). The RRC lower layer 516 is responsible for configuring lower layers and obtaining radio resources (i.e., radio bearers) using RRC signaling between the eNB and the UE.

6 is a block diagram of an eNB 610 in communication with a UE 650 in an access network. At the DL, upper layer packets from the core network are provided to the controller / processor 675. The controller / processor 675 implements the functionality of the L2 layer. At the DL, the controller / processor 675 may perform header compression, encryption, packet segmentation and reordering, multiplexing between logic and transport channels, and radio resource assignments to the UE 650 based on various priority metrics to provide. The controller / processor 675 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the UE 650.

A transmit (TX) processor 616 implements various signal processing functions for the L1 layer (i.e., the physical layer). The signal processing functions may include coding and interleaving to facilitate forward error correction (FEC) at the UE 650, and various modulation schemes (e.g., Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (M-QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)) to signal constellations. The coded and modulated symbols are then split into parallel streams. Each stream is then mapped to an OFDM subcarrier, multiplexed with a reference signal (e. G., Pilot) in time and / or frequency domain, and then a physical channel carrying a time domain OFDM symbol stream is generated Are combined together using an inverse fast Fourier transform (IFFT). The OFDM stream is spatially precoded to produce a plurality of spatial streams. The channel estimates from channel estimator 674 may be used to determine spatial coding as well as coding and modulation schemes. The channel estimate may be derived from the channel condition feedback and / or the reference signal transmitted by the UE 650. Each spatial stream is then provided to another antenna 620 via an individual transmitter 618TX. Each transmitter 618TX modulates the RF carrier into a respective spatial stream for transmission.

At the UE 650, each receiver 654RX receives a signal via its respective antenna 652. [ Each receiver 654RX reconstructs the modulated information on the RF carrier and provides this information to a receive (RX) processor 656. [ The RX processor 656 implements various signal processing functions of the L1 layer. The RX processor 656 performs spatial processing on the information to recover any spatial streams directed to the UE 650. If multiple spatial streams are directed to the UE 650, they may be combined into a single OFDM symbol stream by the RX processor 656. The RX processor 656 then uses Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier and the reference signal may be recovered and demodulated by determining the most likely signal constellation points transmitted by eNB 610. [ These soft decisions may be based on the channel estimates computed by the channel estimator 658. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted by the eNB 610 over the physical channel. The data and control signals are then provided to the controller / processor 659.

Controller / processor 659 implements the L2 layer. The controller / processor may be associated with memory 660, which stores program codes and data. Memory 660 may be referred to as a computer readable medium. At UL, controller / processor 659 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logic channels to recover higher layer packets from the core network. The upper layer packets are then provided to a data sink 662 and the data sink 662 represents all protocol layers over the L2 layer. Various control signals may also be provided to the data sink 662 for L3 processing. Controller / processor 659 is also responsible for error detection using an acknowledgment (ACK) and / or a negative acknowledgment (NACK) protocol to support HARQ operations.

In the UL, a data source 667 is used to provide upper layer packets to the controller / processor 659. Data source 667 represents all protocol layers on the L2 layer. processor 659 is configured to perform header compression, encryption, packet segmentation, and resource allocation based on radio resource assignments by eNB 610, similar to the functionality described with respect to DL transmissions by eNB 610. Controller / Ordering, implementation of the L2 layer for the user plane and the control plane by providing multiplexing between the logic and transport channels. Controller / processor 659 is also responsible for HARQ operations, retransmission of lost packets, and signaling to eNB 610.

Channel estimates derived by the channel estimator 658 from the feedback or reference signal transmitted by the eNB 610 may be used by the TX processor 668 to select appropriate coding and modulation schemes and facilitate spatial processing . The spatial streams generated by TX processor 668 are provided to different antennas 652 via separate transmitters 654TX. Each transmitter 654TX modulates the RF carrier into a respective spatial stream for transmission.

The UL transmission is processed in the eNB 610 in a manner similar to that described with respect to the receiver function at the UE 650. Each receiver 618RX receives a signal via its respective antenna 620. Each receiver 618RX reconstructs the modulated information on the RF carrier and provides this information to the RX processor 670. [ The RX processor 670 may implement the L1 layer.

Controller / processor 675 implements the L2 layer. Controller / processor 675 may be associated with memory 676, which stores program codes and data. Memory 676 may be referred to as a computer readable medium. At UL, controller / processor 675 provides demultiplexing, packet reassembly, decryption, header decompression, control signal processing between transport and logic channels to recover upper layer packets from UE 650 do. The higher layer packets from the controller / processor 675 may be provided to the core network. Controller / processor 675 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

7 is a drawing 750 illustrating an e-mailed multimedia multicast broadcast multimedia service (eMBMS) in a multi-media broadcast (MBSFN) over a single frequency network. The eNBs 752 and 756 of the cells 752 'and 756' may form a first MBSFN region and the eNBs 754 and 756 of the cells 754 'and 756' may form a second MBSFN region can do. (Alternatively, eNBs 756 of cells 756 'may be associated with only one of the first MBSFN region or the second MBSFN region.) The eNBs 752, 754, 756 may be, for example, , And up to a total of eight MBSFN regions. A cell in the MBSFN area can be designated as a reserved cell. For example, cells 756 'in the first and second MBSFN regions may be designated as reserved cells. The reserved cells do not provide multicast / broadcast content, but are time synchronized to cells 752 ', 754' and have limited / reduced power for MBSFN resources to limit interference to MBSFN areas . Each of the eNBs except for the reserved cells of the MBSFN region transmits the same eMBMS control information and data synchronously. Each area may support broadcast, multicast and unicast services. A unicast service is a service intended for a particular user, e.g., a voice call. A multicast service is a service that can be received by a group of users, such as, for example, a subscription video service. A broadcast service is a service that can be received by all users, for example, a news broadcast. Referring to FIG. 7, the first MBSFN region may support a first eMBMS broadcast service, for example, by providing a specific news broadcast to the UE 770. The second MBSFN region may support the second eMBMS broadcast service, for example, by providing different news broadcasts to the UE 760. [ Each MBSFN region supports a plurality of physical multicast channels (PMCHs) (e.g., 15 PMCHs). Each PMCH corresponds to a multicast channel (MCH). Each MCH may multiplex a plurality of (e.g., twenty-nine) multicast logic channels. Each MBSFN region may have one multicast control channel (MCCH). Thus, one MCH can multiplex one MCCH and a plurality of multicast traffic channels (MTCHs), and the remaining MCHs can multiplex a plurality of MTCHs.

As discussed above, the reserved cell is a cell in the MBSFN area that does not contribute to the MBSFN transmission. In the exemplary embodiments, the reserved cell may be allowed to transmit for other services, but the associated MBSFN region (e.g., subframes 1, 2, 3, 6, 7, 8 Or limited to one or more of the subframes 3, 4, 7, 8, 9 for TDD and one or more of the subframes 3, 4, 7, 8, 9 for TDD) . Thus, the reserved cells may not advertise the MBSFN subframe allocations in the system information block (SIB) 2 (SIB2). In addition, the reserved cells may not send the SIB 13 or the physical downlink control channel (PDCCH) to notify the MCCH change. The reserved cells may be known by the network, but may be transparent to the UEs. Thus, the UEs can treat the reserved cells as regular non-MBSFN unicast cells. The connected UEs can monitor the PDCCH on each subframe to check for possible PDSCH / PUSCH allocations and can send a corresponding physical HARQ indicator channel (carrying ACK / NACK feedback) according to the UL HARQ timeline RTI ID = 0.0 > PHICH). ≪ / RTI > The reserved cell may reduce its transmit power to MBSFN resources for the MBSFN region. The reserved cell is an OFDM symbol corresponding to control symbols in MBSFN subframes for the MBSFN region (i.e., corresponding to control symbols for MBSFN services broadcast by neighboring eNBs in MBSFN subframes) Lt; RTI ID = 0.0 > transmit power < / RTI > For example, an eNB that broadcasts MBSFN services may transmit control information of MBSFN subframes on OFDM symbols 0, 1 and PMCH on OFDM symbols 2-11 (consisting of an extended cyclic prefix) . At the same time, the reserved cell can transmit control information at normal power on OFDM symbols 0, 1 and limited / reduced power on OFDM symbols 2-13 (assuming a regular cyclic prefix configuration) box).

의 경우 1, 2 또는 3, 및

의 경우 2, 3 또는 4일 수 있다. PHICH 지속기간은 PDCCH 지속기간에 대한 하한(lower bound)을 제공한다. MBSFN 서브프레임들의 PDCCH 지속기간은,

의 경우 1 또는 2, 및

의 경우 2일 수 있다. 따라서, 이웃 eNB들의 MBSFN 서브프레임들과 동시인, 예비된 셀의 서브프레임들(본 명세서에서는 "예비된 서브프레임들"로 지칭됨)에서, 제어는,

이고 정규의 PHICH 지속기간이 구성되는 경우 1, 2 또는 3개의 OFDM 심볼들;

이고 확장된 PHICH 지속기간이 구성되는 경우 3개의 OFDM 심볼들;

이고 정규의 PHICH 지속기간이 구성되는 경우 2, 3 또는 4개의 OFDM 심볼들; 및

이고 확장된 PHICH 지속기간이 구성되는 경우 3 또는 4개의 OFDM 심볼들에 걸쳐있을 수 있다. 그러나, MBSFN 서브프레임들에 대한 제어는,

이고 정규의 PHICH 지속기간이 구성되는 경우 1 또는 2개의 OFDM 심볼들; 및

또는

이고 확장된 PHICH 지속기간이 구성되는 경우 2개의 OFDM 심볼들에 걸쳐있을 수 있다.The PHICH duration (i.e., the OFDM symbol span) may be quasi-statically configured and may or may not be regular, depending on the configuration specified in the physical broadcast channel (PBCH). The normal PHICH duration may be a non-MBSFN subframe (e.g., zero or more of subframes 0, 4, 5, 9 and subframes 1, 2, 3, 6, 7, 8) And 1 for both MBSFN subframes (e.g., zero or more of subframes 1, 2, 3, 6, 7, 8). The extended PHICH duration may be 3 for non-MBSFN subframes, and 2 for MBSFN subframes. The PDCCH duration of non-MBSFN sub-

1, 2 or 3, and

Lt; / RTI > may be 2, 3 or 4, The PHICH duration provides a lower bound on the PDCCH duration. The PDCCH duration of the MBSFN sub-

1 " or " 2 "

2 < / RTI > Thus, in the reserved subframes of the cell (referred to herein as "reserved subframes"), which is coincident with the MBSFN subframes of the neighboring eNBs,

1, 2 or 3 OFDM symbols when a normal PHICH duration is constructed;

Three OFDM symbols when the extended PHICH duration is configured;

2, 3 or 4 OFDM symbols when a normal PHICH duration is constructed; And

And may span three or four OFDM symbols if an extended PHICH duration is configured. However, control for MBSFN sub-

One or two OFDM symbols when a normal PHICH duration is constructed; And

or

And may span two OFDM symbols if an extended PHICH duration is configured.

In reserved subframes, the reserved cell is allocated at normal power on control / data symbols that conflict with control symbols in MBSFN subframes of the MBSFN region, and on control / data symbols that conflict with PMCH symbols Can be transmitted with limited / reduced power. If the extended PHICH duration is configured, the third control symbol of the reserved subframes may always collide with the PMCH symbols of the MBSFN subframes. For example, if the control symbols span two OFDM symbols in the MBSFN subframes and three OFDM symbols in the reserved subframes, then the reserved cell is the first and second OFDM symbols of the reserved subframes Lt; RTI ID = 0.0 > OFDM < / RTI > of the reserved subframes.

Rather than varying the power across the OFDM symbols within the reserved subframes, the reserved cell can always transmit with limited / reduced power in the reserved subframes. Thus, the reserved cell power variation may be between OFDM symbols in reserved subframes or reserved subframes or reserved subframes. The reserved cell power variation is less than the traffic-to-pilot (T / P) ratio signaled (semi-statically) by automatic gain control (AGC) gain adjustment problems and / / P ratio. ≪ / RTI > For AGC gain, the UEs can determine the energy of the reserved symbols and adjust the AGC gain based on the determined energy. UEs may unnecessarily boost the AGC gain if the energy varies significantly over the symbols, particularly over the subframes, which may result in signal clipping in the normal unicast unicast subframes / ≪ / RTI > For T / P ratios, the UEs can signal the T / P ratio from the reserved cell serving them. The UEs may be configured such that if the decoded signals are received in OFDM symbols based on a single user (SU-MIMO) or multi-user MIMO (MU-MIMO) or modulated based on 16-QAM or 64- The signaled T / P ratio can be used. If the actual T / P ratio of the OFDM symbols varies from the signaled T / P ratio, the UEs may be difficult to decode the control information / data of their OFDM symbols. Thus, methods are needed to reduce UE AGC gain adjustment, decoding errors, and / or other problems associated with cell power changes reserved over subframes / symbols.

8 is a first diagram 800 for illustrating exemplary methods. ENBs 802 in the first MBSFN region broadcast MBSFN services in MBSFN subframes 1, 6, 7 and 8 in radio frame 802 '. The remaining subframes in the radio frame 802 'carry unicast transmissions. ENBs 804 in the second MBSFN region broadcast MBSFN services in MBSFN subframes 1, 2 and 3 in radio frame 804 '. The remaining subframes in radio frame 804 'carry unicast transmissions. The eNB 806 in the reserved cell 806 " may be in the first MBSFN region, the second MBSFN region, or both the first and second MBSFN regions. According to an exemplary method, the eNB 806, in a radio frame, determines subframes used by one or more neighboring eNBs 802 and / or 804 to broadcast MBSFN services. For example, if neighboring eNBs 802 use subframes 1, 6, 7 and 8 to broadcast MBSFN services and neighboring eNBs 804 use subframes 1, 6, 7 and 8 to broadcast MBSFN services, , 2, and 3, the eNB 806 determines that subframes 1, 2, 3, 6, 7, and 8 are used by neighboring eNBs 802, 804 to broadcast MBSFN services . The eNB 806 may then configure one or more of the subframes 1, 6, 7, 8 as reserved subframes, or one or more of the subframes 1, 2, 3 as a reserved subframe Frames, or to configure one or more of the subframes 1, 2, 3, 6, 7, 8 or more as reserved subframes. It is assumed that eNB 806 determines to configure subframes 1, 2, 3, 6, 7, 8 of radio frame 806 'as reserved subframes. Upon determination of the reserved subframes in the radio frame 806 ', the eNB 806 may send to the UE 808 information 810 indicating the reserved subframes. Based on the received information 810, the UE 808 may adjust the AGC gain (812).

The determined subframes 1, 2, 3, 6, 7 and 8 may be referred to as reserved subframes. In the reserved subframes, the eNB 806 may change the power of the unicast DL transmission 814 to the UE 808. In the first configuration, the eNB 806 is configured with normal power in the unspecified unicast subframes 0, 4, 5 and 9 and with limited power in the reserved subframes 1, 2, 3, 6, / Reduced power (814). In the second configuration, the eNB 806 receives normal power in unspecified unicast subframes 0, 4, 5, and 9, and regular power in reserved subframes 1, 2, 3, 6, 7, Lt; / RTI > and both limited / reduced power (814). In this configuration, in the OFDM symbols in the reserved subframes that collide with the OFDM symbols carrying control information from the neighboring eNBs 802 and 804, the eNB 806 transmits (814) with normal power, ENB 806 transmits (814) limited / reduced power in the OFDM symbols in the reserved subframes that collide with the OFDM symbols carrying the PMCH from neighboring eNBs 802 and 804.

The information 810 may also indicate a power change between the reserved subframes and the non-reserved subframes and / or a power change between the symbols in the reserved subframes. The power change information in the information 810 may include information indicating a difference between normal power and limited / reduced power, a difference between normal power and limited / reduced power, a ratio of normal power to limited / Lt; RTI ID = 0.0 > limited / reduced < / RTI > power transmissions. The UE 808 may adjust its AGC gain based on the received power change information (812). In addition to power changes, information 810 may also indicate a T / P ratio for control information / data received with limited / reduced power in OFDM symbols / subframes. If the limited / reduced power DL transmissions 814 are based on SU-MIMO, MU-MIMO, 16-QAM or 64-QAM, And may decode limited / reduced power DL transmissions 814 based on both power change information.

In one configuration, eNB 806 does not transmit information 810 indicating the reserved subframes, power change information, and T / P ratio for limited / reduced power transmissions. In this configuration, the UE 808 does not perform step 812. [ Rather, the eNB 806 may transmit AGC gain adjustment problems and decoding problems at the UE 808 (when the DL transmissions 814 are based on SU-MIMO, MU-MIMO, 16-QAM or 64- Lt; RTI ID = 0.0 > 814 < / RTI > ENB 806 may limit the amount of power allocated to DL transmissions 814 to be less than the threshold value for DL transmissions 814 such that the difference between the normal power and the limited / And determines limited / reduced power based on the power (816). If the DL transmissions 814 are based on SU-MIMO, MU-MIMO, 16-QAM or 64-QAM, then AGC gain adjustment problems associated with the actual T / P ratio being less than the signaled T / The threshold may be determined based on the performance loss allowed in the UE 808 due to problems.

ENB 806 may also attempt to align the control information of the reserved subframes 1, 2, 3, 6, 7, 8 with the control information of the MBSFN subframes of neighboring eNBs 802, 804 have. For example, if neighboring eNBs 802 and 804 have a PDCCH duration of two, eNB 806 may attempt to configure a PDCCH duration of two or less. By aligning the control information, the UE 808 will not have any performance loss associated with the reception and decoding of the control information. In addition, the eNB 806 may attempt to construct a PDCCH duration that is the same as the PDCCH duration of the neighboring eNBs 802, 804. By constructing the same PDCCH duration, the actual T / P over the OFDM symbols carrying the PDSCH will be the same. As part of the alignment of the control information, the eNB 806 may suppress constructing the extended PHICH duration (e.g., three OFDM symbols) and may be configured to maintain a normal PHICH duration OFDM symbol). ≪ / RTI > Assuming that there are less than two OFDM symbols carrying control information in the MBSFN subframes, constructing the extended PHICH duration may be accomplished by arranging the alignment of the control information of the reserved subframes using the control information of the MBSFN subframes . eNB 806 may also schedule UE 808 to QPSK rank 1 single user transmissions in reserved subframes to avoid T / P change problems.

As discussed above, in the first configuration, the eNB 806 may display its reserved subframes and may transmit the T / P ratio and power change information for the limited / reduced DL transmissions to the UE 808, As shown in FIG. The information provided to the UE 808 may be used by the UE 808 to determine which OFDMA symbols are associated with the reserved subframes (i.e., between the reserved subframes and the remaining subframes and / 0.0 > AGC gain < / RTI > In a second configuration, the reserved subframes may be completely transparent to the UE 808. [ In a second configuration, the eNB 806 may limit the reduction of the power of DL transmissions (e. G., To reduce the negative impact on AGC gain adjustment and decoding due to power changes associated with reserved subframes) To keep the difference between the limited / reduced power and the normal power below the threshold) and to align the control symbols of the reserved subframes with the control symbols of the MBSFN subframes of one or more neighboring eNBs And may attempt to schedule single user QPSK rank 1 transmissions. In a third configuration, eNB 806 may not be configured as a reserved cell. In a third configuration, eNB 806 does not transmit control information / data with limited / reduced power for subframes that are coincident with the MBSFN subframes of one or more neighboring eNBs. By not limiting / decreasing its power, UE 808 does not face AGC gain adjustment and decoding problems due to power changes.

9 is a second diagram 900 for illustrating exemplary methods. As discussed above, a reserved cell may transmit control information / data with normal power in unbuffered unicast subframes and limited / reduced power in reserved subframes. Alternatively, in the reserved subframes, the reserved cell may transmit control information / data at normal power in OFDM symbols overlapping / colliding with OFDM symbols of MBSFN subframes carrying control information , Control information / data can be transmitted with limited / reduced power in OFDM symbols overlapping / colliding with OFDM symbols of MBSFN subframes carrying the PMCH. This power change over the OFDM symbols of the reserved subframes is shown in FIG.

As shown in FIG. 9, it is assumed that the reserved cell determines that neighboring eNBs are using subframes 1, 2, 3, 6, 7, 8 to broadcast MBSFN services. Thus, for a reserved cell, subframes 1, 2, 3, 6, 7, 8 of radio frame 902 may be treated as reserved subframes with power changes over OFDM symbols. In addition, in the case of reserved subframes, the reserved cell is transmitted by neighboring eNBs with two OFDM symbols of control information and 10 OFDM symbols of the PMCH (12 total OFDM symbols in the extended cyclic prefix configuration) . The subframes 904, 906, 908 are shown as 14 OFDM symbols in a regular cyclic prefix configuration. In sub-frame 904, the PDCCH / PHICH duration is three OFDM symbols. In the subframe 904, the reserved cell has control information at normal power in OFDM symbols 0, 1, control information at limited / reduced power in OFDM symbol 2, and limited / Data (e. G., PDSCH) with reduced power. In sub-frame 906, the PDCCH / PHICH duration is two OFDM symbols. In sub-frame 906, the reserved cell transmits data at regular power in OFDM symbols 0, 1, and limited / reduced power in OFDM symbols 2-13. For subframe 906, the limited / reduced power may be equal to zero, and thus the reserved cell may not transmit any data. In sub-frame 908, the PDCCH / PHICH duration is one OFDM symbol. In the subframe 908, the reserved cell is used to transmit control information at regular power in OFDM symbol 0, data at normal power in OFDM symbol 1, and data at limited / reduced power in OFDM symbols 2-13 .

10 is a flowchart 1000 of a first method of wireless communication. The method may be performed by the base station / eNB, such as the reserved cell 806. [ In step 1002, the base station determines, in a radio frame, the subframes used by one or more neighbor base stations to provide (e.g., broadcast) services. In step 1004, the base station transmits information indicating the determined subframes to the UE. The information may further indicate a power change between the determined subframes in the radio frame and the remaining subframes and / or between the symbols in the determined subframes. In step 1006, the base station may transmit the first set of control information and / or data of symbols in the determined subframes at a first power. At step 1008, the base station may transmit control information and / or data of the second set of symbols at each of the determined subframes at a second power. The first power may be equal to the second power. In this configuration, at step 1010, the base station may transmit the remaining subframes of the radio frame other than the determined subframes of the radio frame with a third power that is greater than the first power and the second power. The second power may be less than the first power. In this configuration, at step 1012, the base station may transmit the remaining subframes of the radio frame other than the determined subframes of the radio frame with the first power. After step 1012, the base station may continue to point A, which continues in FIG. The determined subframes may coincide with the MBSFN subframes used by one or more neighboring base stations. The symbols may be OFDM symbols.

For example, referring to Figures 8 and 9, the eNB 806 may allocate subframes 1, 2, 3, 6, and 7 of a radio frame by neighboring eNBs 802 and 804 to broadcast MBSFN services. , 8 can be determined to be used. The eNB 806 may then determine that subframes 1, 2, 3, 6, 7, 8 are reserved subframes in the radio frame 806 '. The eNB 806 sends to the UE 808 information 810 indicating the determined / reserved subframes 1, 2, 3, 6, 7, Information 810 may be transmitted between the reserved subframes 1, 2, 3, 6, 7, 8 of radio frame 806 'and the remaining subframes 0, 4, 5, 9 and / 1, 2, 3, 6, 7, and 8, respectively. eNB 806 may transmit control information and / or data in a first set of symbols at a first power in each of the reserved subframes. The first set of symbols may be OFDM symbols colliding with or contemporaneously with the control symbols in the MBSFN subframes of the neighboring eNBs 802, 804. The eNB 806 may transmit control information and / or data of the second set of symbols at each of the determined subframes at a second power. The second set of symbols may be OFDM symbols colliding with or contemporaneous with the PMCH symbols in the MBSFN subframes of neighboring eNBs 802, The first power may be the same as the second power, and both the first power and the second power may be limited / reduced power. In this configuration, the eNB 806 transmits control information / data for the reserved subframes 1, 2, 3, 6, 7, 8 at limited / reduced power (equal to first power and second power) And transmit the control information / data of the remaining non-reserved subframes 0, 4, 5, 9 as the third power. The third power may be equal to the normal unrestricted / non-reduced power. If the second power is less than the first power, the second power may be limited / reduced power, and the first power may be normal unrestricted / non-reduced power. The subframes 904, 906, 908 illustrate this power variation over OFDM symbols for transmission of control information / data in the reserved subframes.

11 is a flowchart 1100 of a second method of wireless communication. The method may be performed by a base station / eNB, such as eNB 806. In step 1102, the base station determines, in a radio frame, the sub-frames used by one or more neighboring base stations to provide services. In step 1104, the base station transmits at the first power in the remaining subframes other than the determined subframes of the radio frame. In step 1114, the base station determines a second power that is less than the first power based on the first power such that the difference between the second power and the first power is less than the threshold. In step 1116, the base station transmits at a second power in a subset of the symbols of the determined subframes. After step 1116, the base station may continue to point A, which continues in FIG.

8, the eNB 806 may receive subframes 1, 2, 3, 6, 7, 8 of a radio frame by eNBs 802, 804 to broadcast MBSFN services. Can be used. The eNB 806 may then determine that subframes 1, 2, 3, 6, 7, 8 are reserved subframes in the radio frame 806 '. The eNB 806 receives the first power (e.g., the first power) in the remaining subframes 0, 4, 5, 9 other than the reserved subframes 1, 2, 3, 6, 7, 8 of the radio frame 806 ' , Normal unrestricted / non-reduced power). eNB 806 may determine a second power (e.g., limited / reduced power) based on the first power such that the difference between the second power and the first power is less than a threshold. The eNB 806 may transmit the control information / data of the subset of symbols at the second power in the reserved subframes 1, 2, 3, 6, 7, A subset of the symbols includes OFDM symbols colliding with or contemporaneously with the PMCH symbols of the MBSFN subframes of the eNBs 802, 804. It is assumed that the eNBs 802 and 804 transmit control information in OFDM symbols 0 and 1 in MBSFN subframes 1, 2, 3, 6, 7 and 8 and PMCH in OFDM symbols 2-11. In a first configuration, the eNB 806 may transmit control information / data at a second power on all OFDM symbols 0-13 of the reserved subframes 1, 2, 3, 6, 7, In a second configuration, the eNB 806 receives the control information / data as a first power on OFDM symbols 0, 1 of the reserved subframes 1, 2, 3, 6, 7, 8, May transmit with a second power on OFDM symbols 2-13 of frames 1, 2, 3, 6, 7, 8.

In steps 1110 and 1112, the base station may attempt to align the control symbols of the reserved subframes with the control symbols of the MBSFN subframes. Specifically, in step 1110, the base station may determine a number of symbols for transmitting control information in each of the determined subframes used by one or more neighbor base stations. In step 1112, the base station may determine to use fewer or more symbols than the determined number of symbols to transmit the control information. In step 1106, to align the control symbols of the reserved subframes with the control symbols of the MBSFN subframes, the base station may configure the extended PHICH duration (e.g., with an OFDM symbol span of 3) , And instead can configure a normal PHICH duration (e.g., with an OFDM symbol span of 1). In step 1108, if the UE uses the signaled T / P ratio to decode signals received via SU-MIMO, MU-MIMO, 16-QAM or 64-QAM, To avoid the problem, one may attempt to schedule UEs with QPSK rank 1 single user transmissions in determined subframes. The limited / reduced power results in a lower T / P ratio than the signaled T / P ratio (which can not be dynamically changed), leading to problems in decoding.

12 is a flowchart 1200 of a third method of wireless communication. The method may be performed by a base station / eNB, such as eNB 806. Fig. 12 continues from point A of Figs. 10 and 11. Fig. In step 1202, the base station may determine symbols for transmitting control information in each of the determined subframes used by one or more neighbor base stations. The determined symbols of each of the determined subframes are the first set of symbols and the remaining symbols of each determined subframe are the second set of symbols. If the PDCCH / PHICH duration of the base station is greater than the PDCCH / PHICH duration of one or more neighboring eNBs, then path 1204 is followed. In step 1210, the base station transmits control information to the first power in the first set of symbols. In step 1212, the base station transmits control information at a second power in a first subset of the symbols in the second set of symbols. In step 1214, the base station transmits data at a second power in a second subset of the symbols in the second set of symbols. For example, referring to subframe 904 of FIG. 9, the PDCCH / PHICH duration of the base station is three OFDM symbols, and the PDCCH / PHICH duration of one or more neighboring eNBs is two OFDM symbols I suppose. A path 1204 may then be followed. Following path 1204, the base station transmits control information at OFDM symbols 0, 1 to first power (the first set of symbols includes symbols 0, 1 coincident with MBSFN control symbols) ). The base station transmits control information from OFDM symbol 2-13 of OFDM symbols 2-13 to a second power (the second set of symbols includes symbols 2-13 concurrent with MBSFN PMCH symbols). The base station transmits data from the OFDM symbols 3-13 of the OFDM symbols 2-13 to the second power.

If the PDCCH / PHICH duration of the base station is equal to the PDCCH / PHICH duration of one or more neighboring eNBs, then path 1208 is followed. In step 1222, the base station transmits control information to the first power in the first set of symbols. In step 1224, the base station transmits data in the second set of symbols to the second power. The second power may be equal to zero such that no data is transmitted in the second set of symbols. For example, referring to subframe 906 of FIG. 9, the PDCCH / PHICH duration of the base station is two OFDM symbols, and the PDCCH / PHICH duration of one or more neighboring eNBs is also two OFDM symbols . Next, path 1208 will follow. Following path 1208, the base station transmits control information from OFDM symbols 0, 1 to the first power. The base station transmits the data at OFDM symbols 2-13 to the second power.

If the PDCCH / PHICH duration of the base station is less than the PDCCH / PHICH duration of one or more neighboring eNBs, then path 1206 is followed. In step 1216, the base station transmits control information at the first power in the first subset of symbols in the first set of symbols. In step 1218, the base station transmits data at the first power in a second subset of the symbols in the first set of symbols. In step 1220, the base station transmits data at a second power in a second set of symbols. For example, referring to sub-frame 908 of FIG. 9, the PDCCH / PHICH duration of the base station is one OFDM symbol, and the PDCCH / PHICH duration of one or more neighboring eNBs is two OFDM symbols I suppose. Next, path 1206 will follow. Following path 1206, the base station transmits control information from the OFDM symbol 0, OFDM symbol 0, to the first power. The base station transmits data at OFDM symbols 0, 1 OFDM symbol 1 to the first power. The base station transmits the data at OFDM symbols 2-13 to the second power.

13 is a flowchart 1300 of a fourth method of wireless communication. The method may be performed by a UE, such as the UE 808. In step 1302, the UE receives, from a base station, information indicative of subframes used by one or more neighboring base stations in a radio frame to provide services. In step 1306, the UE adjusts the AGC gain based on the displayed subframes. The information may further include a power change between at least one of the subframes displayed in the radio frame and the remaining subframes or between the symbols in the displayed subframes. In this configuration, the AGC gain can be adjusted based further on the power change. In step 1304, the UE may receive control information without data in the indicated subframes, and control information and data in the remaining subframes in the radio frame. The AGC gain of step 1306 may be adjusted based on the symbols carrying control information in the indicated subframes and the symbols carrying control information and data in the remaining subframes. In step 1308, the UE may receive a T / P ratio. In step 1310, the UE may receive information indicative of a power change between the displayed subframes in the radio frame and the remaining subframes and / or between the symbols in the displayed subframes. In step 1312, the UE may decode the received data based on the T / P ratio and power variation. The indicated subframes may coincide with MBSFN subframes used by one or more neighboring base stations to provide services.

8, a UE 808 may receive subframes 1, 2, 3, 6, 7, 8 of a radio frame by eNBs 802, 804 to broadcast MBSFN services. From the eNB 806, information 810 indicating that it is used. UE 808 may then determine that subframes 1, 2, 3, 6, 7, 8 in radio frame 806 'are reserved subframes. The UE 808 may adjust the AGC gain based on the reserved subframes 1, 2, 3, 6, 7, 8 (812). Information 810 may be transmitted between the subframes 1, 2, 3, 6, 7, 8 reserved in radio frame 806 'and the remaining subframes 0, 4, 5, 9 and / 1, 2, 3, 6, 7, 8, respectively. 9, in a subframe 906, the UE 808 is configured to transmit, in the radio frame 902, data without any data in the reserved subframes 1, 2, 3, 6, 7, / Reduced power is zero) control information, and the remaining subframes 0, 4, 5, 9 can receive control information and data. The AGC gain is calculated from OFDM symbols 0,1 carrying the control information in the reserved subframes 1, 2, 3, 6, 7, 8 and control information and data in the remaining subframes 0, 4, 5, RTI ID = 0.0 > OFDM < / RTI > The UE 808 receives the reserved subframes 1, 2, 3, 6, 7, 8 and the remaining subframes 0, 4, 5, 9 and / Information indicating the power change between OFDM symbols in frames 1, 2, 3, 6, 7, 8, and T / P ratio. The UE 808 may decode the data received in the reserved subframes 1, 2, 3, 6, 7, 8 based on the power change and the T / P ratio.

14 is a conceptual data flow diagram 1400 illustrating the flow of data between different modules / means / components in an exemplary eNB / base station device 1402. The base station includes a reserved sub-frame determination module 1404 that can determine, in a radio frame, the sub-frames used by one or more neighboring base stations to provide services. The reserved subframe determination module may be configured to provide one or more neighboring base stations (e.g., via a backhaul connection) or one or more neighboring base stations to provide services via information provided by some other network entity Frames that are used by neighboring base stations of the base station. The reserved subframe determination module 1404 may provide the subframe information reserved for the transmission module 1406 and the transmission module 1406 may transmit to the UE 1450 information indicative of the determined subframes. The information may further indicate a power change between the determined subframes in the radio frame and the remaining subframes and / or between the symbols in the determined subframes. The information can further display the T / P ratio. The reserved sub-frame determination module 1404 may provide the reserved sub-frame information to the power control module 1408 and the power control module 1408 may determine the first power and the second power. The power control module 1408 may provide the determined power information to the transmitting module 1406 and the transmitting module 1406 may transmit control information and / or data of the first set of symbols in each of the determined subframes to the first And transmit the second set of control information and / or data of symbols in the determined subframes at a second power. The first power may be equal to the second power. In this configuration, the power control module 1408 may determine the third power and may provide the power information to the transmitting module 1406, and the transmitting module 1406 may determine that the radio Frames of the frame at a third power greater than the first power and the second power. The second power may be less than the first power. In this configuration, the transmitting module 1406 may transmit the remaining subframes of the radio frame other than the determined subframes of the radio frame with the first power.

The reserved sub-frame determination module 1404 may determine symbols for transmitting control information in each of the determined sub-frames used by one or more neighboring base stations. The determined symbols of each of the determined subframes may be a first set of symbols and the remaining symbols of each of the determined subframes may be a second set of symbols. If the PDCCH / PHICH duration of the base station is greater than the PDCCH / PHICH duration of one or more neighbor BSs, then the transmitting module 1406 may transmit control information from the first set of symbols to the first power, The second subset of symbols may transmit control information at a second power and the second subset of symbols may transmit data at a second power. If the PDCCH / PHICH duration of the base station is equal to the PDCCH / PHICH duration of one or more neighboring base stations, the transmitting module 1406 may transmit control information to the first power in the first set of symbols, And transmit data at a second power in the second set of symbols. The second power may be equal to zero such that no data is transmitted in the second set of symbols. If the PDCCH / PHICH duration of the base station is less than the PDCCH / PHICH duration of one or more neighboring base stations, then the transmitting module 1406 controls the first power in the first subset of symbols And may transmit data at a first power in a second subset of symbols of the first set of symbols and transmit data at a second power in a second set of symbols. The determined subframes may be concurrent with the MBSFN subframes used by one or more neighboring base stations. The symbols may be OFDM symbols.

The reserved sub-frame determination module 1404 may determine, in a radio frame, the sub-frames used by one or more neighboring base stations to provide services. The reserved sub-frame determination module 1404 may provide the reserved sub-frame information to the power control module 1408 and the transmission module 1406. [ The power control module 1408 may determine a first power for transmitting control information and / or data. The power control module 1408 may provide the determined power information to the transmitting module 1406 and the transmitting module 1406 may transmit the determined power information in the remaining subframes other than the determined subframes in the radio frame have. The power control module 1408 may determine the second power based on the first power such that the difference between the second power and the first power is less than a threshold. The second power may be less than the first power. The power control module 1408 may provide the determined power information to the transmitting module 1408 and the transmitting module 1408 may transmit with the second power in a subset of the symbols of the determined subframes.

The reserved sub-frame determination module 1404 may provide the reserved sub-frame information to the alignment, configuration and scheduling module 1410. [ Alignment, configuration, and scheduling module 1410 may determine a number of symbols for transmitting control information in each of the determined subframes used by one or more neighboring base stations, and for transmitting control information, It may be determined to use fewer or more symbols than the determined number of symbols. Alignment, configuration and scheduling module 1410 may inhibit configuring the extended PHICH duration and instead configure a normal PHICH duration. Alignment, configuration and scheduling module 1410 may attempt to schedule UEs with QPSK rank 1 single user transmissions in determined subframes.

The apparatus may include additional modules that perform each of the steps of the algorithm in the above-described flowcharts of Figs. 10-12. Thus, each step in the above-described flowcharts of FIGS. 10-12 may be performed by a module, and the device may include one or more of these modules. The modules may be one or more hardware components configured to perform the mentioned processes / algorithms, or may be implemented by a processor configured to perform the mentioned processes / algorithms, or may be implemented by a processor Readable medium, or some combination thereof. ≪ RTI ID = 0.0 >

Figure 15 is a drawing 1500 illustrating an example of a hardware implementation for an eNB device 1402 ' using a processing system 1514. [ Processing system 1514 may be implemented with a bus architecture generally represented by bus 1524. [ The bus 1524 may include any number of interconnect busses and bridges, depending on the particular application of the processing system 1514 and overall design constraints. Bus 1524 may include various circuits including one or more processors and / or hardware modules represented by processor 1504, modules 1404, 1406, 1408, 1410 and computer readable medium 1506, Links together. The bus 1524 can also link various other circuits, such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art and will not be described any further .

The processing system 1514 may be coupled to the transceiver 1510. Transceiver 1510 is coupled to one or more antennas 1520. Transceiver 1510 provides a means for communicating with various other devices via a transmission medium. The processing system 1514 includes a processor 1504 coupled to a computer readable medium 1506. Processor 1504 is responsible for general processing, including the execution of software stored on computer readable medium 1506. The software, when executed by the processor 1504, causes the processing system 1514 to perform the various functions described above for any particular device. Computer readable medium 1506 may also be used to store data that is operated by processor 1504 when executed by software. The processing system further includes at least one of the modules 1404, 1406, 1408, and 1410. The modules may include one or more hardware modules coupled to the processor 1504, or any combination thereof, executed by the processor 1504 and resident / stored in the computer readable medium 1506 . The processing system 1514 may be a component of the eNB 610 and may include at least one of a TX processor 616, an RX processor 670 and a controller / processor 675 and / or a memory 676.

In a first configuration, a device 1402/1402 'for wireless communication includes means for determining, in a radio frame, subframes used by one or more neighboring base stations to provide services. The apparatus further comprises means for transmitting to the UE information indicative of the determined subframes. The apparatus comprises means for transmitting at least one of control information or data of a first set of symbols in each of the determined subframes at a first power and means for transmitting control information or data of a second set of symbols in each of the determined subframes And means for transmitting at least one to the second power. The first power may be equal to the second power. In this arrangement, the apparatus further comprises means for transmitting the remaining subframes of the radio frame other than the determined subframes of the radio frame with a third power greater than the first power and the second power. The second power may be less than the first power. In this arrangement, the apparatus further comprises means for transmitting the remaining sub-frames of the radio frame other than the determined sub-frames of the radio frame with the first power. The apparatus may further comprise means for determining symbols for transmitting control information in each of the determined subframes used by one or more neighboring base stations. The determined symbols of each of the determined subframes may be a first set of symbols and the remaining symbols of each of the determined subframes may be a second set of symbols. Wherein the means for transmitting in the first set of symbols and in the second set of symbols in each of the determined subframes comprises means for transmitting control information in a first set of symbols to a first power, Means for transmitting control information at a second power in a first subset and means for transmitting data at a second power in a second subset of symbols in the second set of symbols. Wherein the means for transmitting in the first set of symbols and in the second set of symbols in each of the determined subframes comprises means for transmitting control information to the first power in a first set of symbols, 2 power. ≪ / RTI > Wherein the means for transmitting in the first set of symbols and in the second set of symbols in each of the determined subframes comprises means for transmitting control information at a first power in a first subset of symbols of the first set of symbols, Means for transmitting data at a first power in a second subset of the first set of symbols and means for transmitting data at a second power in a second set of symbols. The aforementioned means may be one or more of the aforementioned modules of the processing system 1514 and / or the device 1402 of the device 1402 'configured to perform the functions listed by the means described above. As described above, the processing system 1514 may include a TX processor 616, an RX processor 670, and a controller / processor 675. Thus, in one configuration, the aforementioned means may be a TX processor 616, an RX processor 670 and a controller / processor 675 configured to perform the functions listed by the means described above.

In a second configuration, a device 1402/1402 'for wireless communication comprises means for determining a plurality of symbols for transmitting control information in each of the determined subframes used by one or more neighboring base stations And means for determining to use fewer than the determined number of symbols or the same number of symbols to transmit the control information. The apparatus may further comprise means for inhibiting configuring the extended PHICH duration. The apparatus may further comprise means for scheduling UEs with QPSK rank 1 single user transmissions in determined subframes. The apparatus may further comprise means for determining symbols for transmitting control information in each of the determined subframes used by one or more neighboring base stations. The determined symbols of each of the determined subframes may be a first set of symbols and the remaining symbols of each of the determined subframes may be a second set of symbols. The apparatus may further comprise means for transmitting control information to the first power in the first set of symbols. Wherein the means for transmitting at a second power in a subset of the symbols of the determined subframes comprises means for transmitting control information at a second power in a first subset of symbols of the second set of symbols, And means for transmitting data at a second power in a second subset of the symbols. The apparatus may further comprise means for transmitting control information to the first power in the first set of symbols. The means for transmitting at a second power in a subset of the symbols of the determined subframes may comprise means for transmitting data at a second power in a second set of symbols. The apparatus comprises means for transmitting control information at a first power in a first subset of symbols in a first set of symbols and means for transmitting control information at a first power in a second subset of symbols in a first set of symbols, And < / RTI > The means for transmitting at a second power in a subset of the symbols of the determined subframes may comprise means for transmitting data at a second power in a second set of symbols. The aforementioned means may be one or more of the aforementioned modules of the processing system 1514 and / or the device 1402 of the device 1402 'configured to perform the functions listed by the means described above. As described above, the processing system 1514 may include a TX processor 616, an RX processor 670, and a controller / processor 675. Thus, in one configuration, the aforementioned means may be a TX processor 616, an RX processor 670 and a controller / processor 675 configured to perform the functions listed by the means described above.

FIG. 16 is a conceptual data flow diagram 1600 illustrating the flow of data between different modules / means / components in an exemplary UE device 1602. The UE 1602 includes a receiving module 1604 that receives control information / data from a base station 1650 and includes, in a radio frame, a subframe used by one or more neighboring base stations to provide services, Can be received from the base station. The receiving module 1604 may provide the reserved subframe information to the reserved subframe determining module 1606 and the reserved subframe determining module 1606 determines which subframes are reserved subframes . The reserved sub-frame determination module 1606 may provide the reserved sub-frame information to the AGC gain adjustment module 1608. [ Receive module 1604 may provide control information / data to AGC gain adjustment module 1608. [ AGC gain adjustment module 1608 may adjust the AGC gain based on the displayed subframes. The received information may further include, in a radio frame, a power change between at least one of the displayed sub-frames and the remaining sub-frames, or between symbols in the displayed sub-frames. Receive module 1604 may provide power change information to AGC gain adjustment module 1608 and AGC gain adjustment module 1608 may adjust the AGC gain based further on the power change. Receive module 1604 may receive control information in data frames in the indicated subframes and control information and data in the remaining subframes in the radio frame. In this configuration, the AGC gain adjustment module 1608 may adjust the AGC gain based on the symbols carrying the control information in the indicated sub-frames and the symbols carrying control information and data in the remaining sub-frames . Receive module 1604 may receive the T / P ratio from base station 1650. [ Receive module 1604 may receive information indicative of a change in power between at least one of the displayed subframes and the remaining subframes or between symbols in the displayed subframes in a radio frame. Receive module 1604 may provide T / P ratio and power change information to decoding module 1610 and decoding module 1610 may decode the received data based on T / P ratio and power change information . The indicated subframes may coincide with MBSFN subframes used by one or more neighboring base stations to provide services.

The apparatus may include additional modules that perform each of the steps of the algorithm in the above-described flowchart of Fig. Thus, each step in the above-described flowchart of FIG. 13 may be performed by a module, and the device may include one or more of these modules. The modules may be one or more hardware components configured to perform the mentioned processes / algorithms, or may be implemented by a processor configured to perform the mentioned processes / algorithms, or may be implemented by a processor Readable medium, or some combination thereof. ≪ RTI ID = 0.0 >

FIG. 17 is a drawing 1700 illustrating an example of a hardware implementation for a UE device 1602 'employing a processing system 1714. Processing system 1714 may be implemented with a bus architecture represented generally as bus 1724. [ The bus 1724 may include any number of interconnect busses and bridges, depending on the particular application of the processing system 1714 and overall design constraints. The bus 1724 may include various circuits including one or more processors and / or hardware modules represented by a processor 1704, modules 1604, 1606, 1608, 1610 and computer readable medium 1706, Links together. Bus 1724 can also link various other circuits, such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art and will not be described any further .

The processing system 1714 may be coupled to the transceiver 1710. Transceiver 1710 is coupled to one or more antennas 1720. Transceiver 1710 provides a means for communicating with various other devices via a transmission medium. The processing system 1714 includes a processor 1704 coupled to a computer readable medium 1706. Processor 1704 is responsible for general processing, including the execution of software stored on computer readable medium 1706. The software, when executed by the processor 1704, causes the processing system 1714 to perform the various functions described above for any particular device. Computer readable medium 1706 may also be used to store data operated by processor 1704 when executed by software. The processing system further includes at least one of modules 1604, 1606, 1608, and 1610. The modules may be software modules executed on processor 1704 and resident / stored in computer readable medium 1706, one or more hardware modules coupled to processor 1704, or any combination thereof . The processing system 1714 may be a component of the UE 650 and may include at least one of a TX processor 668, an RX processor 656 and a controller / processor 659 and / or a memory 660.

In one configuration, a device 1602/1602 'for wireless communication is configured to receive, in a radio frame, information indicative of subframes used by one or more neighboring base stations to provide services from a base station Means. The apparatus further comprises means for adjusting the AGC gain based on the displayed sub-frames. The apparatus may further comprise means for receiving control information in the radio frame, no data in the indicated subframes, and control information and data in the remaining subframes. In this configuration, the AGC gain is adjusted based on symbols carrying control information in the indicated subframes, and symbols carrying control information and data in the remaining subframes. The apparatus comprises means for receiving a T / P ratio, receiving information indicative of a change in power between at least one of the displayed subframes and the remaining subframes, or between symbols in the displayed subframes, in a radio frame And means for decoding the received data based on the T / P ratio and the power change. The aforementioned means may be one or more of the aforementioned modules of the processing system 1714 and / or the device 1602 of the device 1602 'configured to perform the functions listed by the means described above. As described above, the processing system 1714 may include a TX processor 668, an RX processor 656, and a controller / processor 659. Thus, in one configuration, the aforementioned means may be a TX processor 668, an RX processor 656 and a controller / processor 659 configured to perform the functions listed by the means described above.

In order to reduce interference to MBSFN signals broadcast by neighboring eNBs, the UE AGC gain adjustment associated with the reserved cell power changes over the subframes / symbols that the reserved cell transmits with limited / reduced power , Methods for reducing decoding errors and / or other problems are provided above. The methods provided may also include UE AGC gain adjustments associated with cell power changes across subframes / symbols that the eNB is transmitting with limited / reduced power, to reduce interference to neighboring eNBs that provide unicast services, And is applicable to heterogeneous networks to reduce decoding errors and / or other problems.

It is understood that the particular order or hierarchy of steps in the disclosed processes is an example of exemplary approaches. It will be appreciated that, based on design priorities, a particular order or hierarchy of steps of the processes may be rearranged. Additionally, some steps may be combined or omitted. The appended method claims present elements of the various steps in an exemplary order, but are not intended to be limited to the particular order or hierarchy presented.

The previous description is provided to enable any person of ordinary skill in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Accordingly, the claims are not intended to be limited to the aspects shown herein, but rather should be accorded the widest possible scope consistent with the scope of the claims, wherein references to singular elements, unless otherwise specifically stated, Quot; and " one "and " more than one ", rather than " Unless specifically stated otherwise, the term "part" refers to one or more. All structural and functional equivalents of the various elements of the elements described throughout this disclosure which are known or later known to those skilled in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims It is intended. Furthermore, any disclosure herein is not intended to be publicly available, whether or not such disclosure is expressly recited in a claim. Elements of any claim are not construed as means plus functions unless the element is explicitly recited using the phrase "means for ".

Claims (18)

A radio communication method of a base station,
In a radio frame, determining subframes used by one or more neighboring base stations to provide services;
Transmitting, in the radio frame, a first power in remaining subframes other than the determined subframes;
Determining the second power based on the first power such that the difference between the first power and the second power is less than a threshold based on a performance loss acceptable to the user equipment, Less than power -; And
And transmitting at the second power in a subset of the symbols of the determined subframes.
A wireless communication method of a base station. The method according to claim 1,
Determining a plurality of symbols in each of the determined subframes that are used by the one or more neighboring base stations to transmit control information; And
Further comprising determining to use fewer or more symbols than the determined number of symbols to transmit control information. The method according to claim 1,
Further comprising suppressing configuring an extended physical hybrid self-repeat request indicator channel (PHICH) duration. The method according to claim 1,
Further comprising scheduling user equipments (UEs) with quadrature phase shift keying (QPSK) rank 1 single user transmissions in the determined subframes. The method according to claim 1,
Further comprising determining symbols in each of the determined subframes that are used by the one or more neighboring base stations to transmit control information,
Wherein the determined symbols in each of the determined subframes are a first set of symbols and the remaining symbols in each of the determined subframes are a second set of symbols. 6. The method of claim 5,
Further comprising transmitting control information from the first set of symbols to the first power,
Wherein the transmitting with the second power in the subset of symbols of the determined subframes comprises:
Transmitting control information to the second power in a first subset of the symbols in the second set of symbols; And
And transmitting data at the second power in a second subset of the symbols in the second set of symbols. 6. The method of claim 5,
Further comprising transmitting control information from the first set of symbols to the first power,
Wherein transmitting with the second power in a subset of the symbols of the determined subframes comprises transmitting data in the second set of symbols with the second power. 6. The method of claim 5,
Transmitting control information to the first power in a first subset of the first set of symbols; And
And transmitting data at the first power in a second subset of the symbols of the first set of symbols,
Wherein transmitting with the second power in a subset of the symbols of the determined subframes comprises transmitting data in the second set of symbols with the second power. A base station apparatus for wireless communication,
Means for determining, in a radio frame, subframes used by one or more neighboring base stations to provide services;
Means for transmitting, in the radio frame, at a first power in the remaining sub-frames other than the determined sub-frames;
Means for determining the second power based on the first power such that the difference between the first power and the second power is less than a threshold based on a performance loss allowed in the user equipment, Less than 1 power -; And
And means for transmitting at the second power in a subset of the symbols of the determined subframes.
Base station apparatus. 10. The method of claim 9,
Means for determining a plurality of symbols in each of the determined subframes, which are used by the one or more neighboring base stations to transmit control information; And
Further comprising means for determining to use less symbols or equal number of symbols than a determined number of symbols to transmit control information. 10. The method of claim 9,
Further comprising means for suppressing configuring an extended physical hybrid self-repeat request indicator channel (PHICH) duration. 10. The method of claim 9,
And means for scheduling user equipments (UEs) with quadrature phase shift keying (QPSK) rank 1 single user transmissions in the determined subframes. 10. The method of claim 9,
Further comprising means for determining symbols in each of the determined subframes used by the one or more neighboring base stations to transmit control information,
Wherein the determined symbols in each of the determined subframes are a first set of symbols and the remaining symbols in each of the determined subframes are a second set of symbols. 14. The method of claim 13,
Further comprising means for transmitting control information from the first set of symbols to the first power,
Wherein the means for transmitting at the second power in the subset of symbols of the determined subframes comprises:
Means for transmitting control information to the second power in a first subset of the symbols in the second set of symbols; And
And means for transmitting data at the second power in a second subset of the symbols in the second set of symbols. 14. The method of claim 13,
Further comprising means for transmitting control information from the first set of symbols to the first power,
Wherein the means for transmitting with the second power in the subset of symbols of the determined subframes comprises means for transmitting data in the second set of symbols with the second power. 14. The method of claim 13,
Means for transmitting control information to the first power in a first subset of the first set of symbols; And
And means for transmitting data at the first power in a second subset of the first set of symbols,
Wherein the means for transmitting with the second power in the subset of symbols of the determined subframes comprises means for transmitting data in the second set of symbols with the second power. A base station apparatus for wireless communication,
In a radio frame, determine subframes used by one or more neighboring base stations to provide services;
In the radio frame, with the first power in the remaining sub-frames other than the determined sub-frames;
Determine a second power based on the first power such that the difference between the first power and the second power is less than a threshold based on a performance loss acceptable to the user equipment, Less than -; And
To transmit at the second power in a subset of the symbols of the determined subframes
Comprising a processing system,
A base station device for wireless communication. A computer readable medium at a base station,
Code in a radio frame for determining subframes used by one or more neighboring base stations to provide services;
A code for transmitting, in the radio frame, first power in remaining subframes other than the determined subframes;
A code for determining the second power based on the first power such that the difference between the first power and the second power is less than a threshold based on a performance loss allowed in the user equipment, Less than 1 power -; And
And a code for transmitting the second power in a subset of the symbols of the determined subframes.
Computer readable medium.

Images